Features

Get a Stake in PVC Fencing

From: Plastics Technology
Issue: July 2000

PVC fence markets are posting rapid gains, prompting profile extruders to install new machines by the dozens and convert existing plants from pipe and siding production. New players are jumping in, too including makers of wood-filled composites.

As occurred in PVC siding and windows a decade ago, fence profiles are now seeing explosive growth and rapid plant expansions, including conversions of entire plants from pipe, siding, and other construction profiles. While demand for all types of fencing typically grows 5-7% a year, the PVC sector has been surging ahead by 20-30% annually, and this year’s growth could hit 50%, according to David Lawrence of Outdoor Advantage in Snohomish, Wash. “The only limiting factor may be the shortage of PVC,” adds the president of this two-year-old start-up, which operates PVC fence-profile plants in Florida and Texas.

Unlike windows and siding, fence makers face few hurdles in the form of building codes or ASTM standards. There are a few notable exceptions. Acoustical fence must meet stringent performance tests. Pool fences and deck rails have to withstand specified lateral loadings. Ranch fence needs to be robust enough to keep horses in. And any fence in Dade County, Fla., must stand up to 120-mph hurricanes. But otherwise, fence requirements are mostly aesthetic, which has helped PVC profiles to become a mainstream product in just a few years. Forty-six percent of the current PVC fence market is in residential fencing, 36% in ranch (post and rail), 12% in encapsulated-metal railings, 4% in decking, and 2% in lawn and garden.

Lots of room to grow

“Fences are at critical mass now, where a lot of processors are doing well and expanding rapidly,” says Harlan Doering, v.p. of Kansas American Tooling, McPherson, Kan., a maker of dies and calibrators for fence profiles. From a standing start in the early 1980s, PVC fence sales grew to about $350 million last year, industry sources say. “The larger market of wood fences is $2 billion a year, so there’s still a lot of replacement potential out there,” says the sales director of one big vinyl fence company.

In the past year alone, Krauss-Maffei Corp., Florence, Ky., says it has delivered 16 conical twin-screw extrusion lines to three PVC fence processors, all of which are running dual strands for maximum output. “Usually with that kind of growth, you’d expect the product to be cheaper than the alternative, but PVC fences are more expensive,” says Michael Riese, product manager at Lawrence McCoy in Worcester, Mass., a distributor of vinyl, wood, and aluminum fences. Even a 10-15% price increase early this year hasn’t dampened sales, he notes.

What triggered this year’s explosive growth is sudden, broad customer acceptance of PVC fences, especially among smaller contractors and buildings-supply houses. They offer PVC as a high-end choice to customers. “There is clearly a shift to maintenance-free building products. It’s not that people love a product that looks plastic,” Riese explains. “But people are not in love with scraping and painting their fences, either, and they’re willing to pay more not to have to do it.”

“Ranch,” or post and rail, is the commodity end of the PVC market, and is the most price-competitive with wood fencing. In fact, some PVC fence makers say they can undersell wood in some cases. At the high end, residential fence sells for 30% to 300% more than wood, depending on the complexity of the fence system. But even in this sector, all the new extrusion capacity flooding the market is starting to depress profit margins, notes William Zell, sales and marketing manager at Westech Fence in Mt. Vernon, Ind.

The explosive growth of PVC fences, even at a price premium to wood, isn’t lost on the makers of wood-composite decks and rails. They are eyeing fences as their next potential market. Wood-flour-filled polyolefins and PVC have already gained acceptance in non-structural profiles for decking and in metal-reinforced railings. They have the advantage of the look and feel of natural woodgrain, which plain PVC fencing can only imitate with streaks of pigment.

Pipe makers converted

Nebraska Plastics Inc. in Cozad, Neb., is considered to have made the first PVC fencing in 1976. “That fence still stands on a farm east of Cozad, Neb.,” notes company president Rex German. Other small PVC pipe makers began to follow suit in the early to mid-’80s, like Triple Crown Fence (now part of Royal Group) in Milford, Ind., and Bufftech (now part of Certainteed) in Buffalo, N.Y. They were drawn by the double-digit profit margins in fencing, as compared with less than 1% margins in pipe.

By 1989, fences were 25% of Bufftech’s sales, and by 1991, Bufftech was out of pipe altogether. Kroy Building Products in York, Neb., was also exclusively a pipe maker until 1990, when it started making PVC fences. By ’96, Kroy had split its pipe and fence making into two companies, of which fencing was much larger.

Makers of window and siding profiles also got into fences as a profitable way to reuse scrap that they could less readily put back into windows and siding. Lumber and building-products companies have also gotten into PVC fences. An example is lumber maker Irwin Industries in Peachtree City, Ga., which began making PVC fence profiles five years ago. “Now other profile companies are looking at fences as an additional product line,” says Tom Brown, sales manager at ExtrusionTek Milacron in Batavia, Ohio.

Picking up the pace

Pipe and siding companies initially approached fence manufacturing quite differently. Pipe makers extruded monolayer products very fast, often with dual-strand dies, and without worrying much about surface cosmetics. They applied high-output pipe cooling techniques such as vacuum sizing, flooded cooling, and high-intensity spray. On the other hand, window-profile makers were used to extruding far more slowly than pipe, with close attention to cosmetics and dimensional tolerances. They used dual-strand lines primarily on smaller profiles, and they typically relied on dry-sizing calibrators. In addition, window-profile makers put uv-resistant cap layers on exposed surfaces of their fence products to reduce their overall use of stabilizers and titanium dioxide.

Now the two approaches are meeting somewhere in the middle: Profile makers are speeding up their fencing lines with use of high-speed pipe cooling and dual-strand lines of all sizes. Coextrusion of uv cap layers is also growing in popularity.

However, there are dissenters. Royal Crown and Nebraska Plastics, for example, are committed to monolayer extrusion, believing it makes a superior fence product. Nebraska Plastics’ German warned about coextrusion at the fence convention in Fla. this year: “Unfortunately, many producers have begun using PVC fence as a dumping ground for inferior materials. While coextrusion itself isn’t the culprit, it gives opportunistic producers the chance to mask inappropriate materials with a capstock.”

“The latest change in the fence business is getting higher capacity machines and running them faster, without the dimensional constraints of window profiles,” says Lawrence of Outdoor Advantage. His firm runs conical twin at over 1200 lb/hr, thanks in part to a very long, 14-ft puller.

As an example of how fast things are changing, just a year ago, standard cooling tanks for PVC fencing pumped 60-100 gal/min of water from 100-150 nozzles, or else used turbulent immersion cooling. But in the past year Conair has delivered several high-intensity spray-cooling tanks for fences that deliver 200-340 gal/min through up to 370 spray nozzles in a 24-ft tank.

“Evaporative cooling, used properly in the initial stage of cooling, can increase cooling 20-30% over immersion,” says Conair product manager Robert Bessemer. Such intensive cooling—combined with a system for air/water separation, vacuum, and water recirculation—has been used on high-output pipe lines for 15 years but is relatively new to fences, he says.

Cooling lines are also getting longer to keep up with higher production rates. Calibrators have gone from 24 to 48 in. long, and flood tanks from 20 to 30 ft, plus in some cases another 10 ft of spray tank. Recently installed fence lines typically use 40 ft of cooling. “In the past year, we’ve probably raised our output 50% by improving the streamlining in dies and adding to the length of dry calibration and wet cooling tanks,” says Kansas American’s Doering.

For extruding fences at 1200-2000 lb/hr, ExtrusionTek Milacron recommends its 80- or 92-mm conical twin-screw for the substrate and a 55-mm conical twin for the cap layer. A standard 1.5 x 5.5 in. fence plank typically runs at up to 16 ft/min, whereas a high-output parallel twin-screw reportedly can push speeds to 30 ft/min while running dual strands.

Davis-Standard expanded its Gemini series of parallel twin-screws last year with a larger 140-mm model that puts out up to 2800 lb/hr of pipe. But so far the biggest Gemini extruder used in fencing is the 114-mm, good for 1600 lb/hr.

Design innovations

PVC fence designs are becoming more elaborate. They developed in the early 1990s from simple posts and slats into complex interlocking systems with tongue-and-groove “privacy panels” and a variety of molded finials and caps.

The big design news at January’s Fence Tech 2000 show in Tampa, Fla., was a 1.5 x 13.4 in. tongue-in-groove privacy panel with eight internal support ribs, which Outdoor Advantage says is the widest fence profile on the market.

Cap layers are blooming with new colors in the past six months. Whereas fences have typically been either white, tan, or gray, Kroy recently added khaki, navy blue, forest green, burgundy, and “Timberlast” woodgrain (made by striping black ink into a monolayer tan or gray profile). Bufftech introduced a marbleized woodgrain effect two years ago.

Most processors of fence profiles are evaluating foam as a way to raise output and possibly gain other attributes like sound deadening. Foam is used in PVC building profiles, but these tend to be light trim pieces, not free-standing ones, because foam reduces PVC’s impact strength, though it can increase stiffness.

Reedy International Corp., Keyport, N.J., recently introduced Safoam RIC-FP chemical blowing agent for PVC. It’s said to have the smallest particle size on the market—7 microns vs. 35 microns for previous products. Reedy sources note that foaming increases throughput by 10-20% because CO2 generated by the blowing agent in the extruder acts as a lubricant or processing aid.

Wood composites next?

The next wave of fence developments is likely to include wood -composites. Wood-filled PVC and polyolefin rails, with and without cap layers, are already commercial, though they are heavier and more expensive than conventional PVC fences. Cap layers give a painted look, but the composites can also be embossed or finished to look like natural woodgrain.

Adding wood flour is a natural progression for current PVC fence makers, because of the greater heat resistance of wood composites. “Hypothetically a wood composite should do better in hot climates,” says Al England, v.p. of Strandex Corp., Madison, Wis., which licenses proprietary wood-composite profile technology that is now widely used for decks and rails.

Meanwhile, makers of wood-composite “plastic lumber” for other applications are being drawn to the fence market. One of these is Comptrusion Corp. in Toronto, a three-year-old maker of wood-filled PVC decking, railing and window profiles. Says v.p. Jim Pratt, “Our initial market analysis was that it would be a stretch for composites to compete with pressure-treated wood fences. But we can compete with plain PVC. I’m glad the PVC fence growth curve is going off the charts, because it will stop people from comparing the cost of plastic alternative fences to wood.” Comptrusion plans to expand production next year in Canada and the U.S. “We’ll be going after the fence market once we get a handle on the volume for the rails and decks—probably next year,” Pratt says. “We’ll look at performance-rated fences like acoustical fence first, which is something PVC alone can’t do.”

Trex Co. in Winchester, Va., which makes nonstructural plastic-lumber decking and slats out of waste wood fibers and reclaimed PE grocery sacks and stretch wrap, also is producing fence slats. “Fencing is a growing application for us and an excellent use for nonstructural components like vertical pickets and slats,” says sales and marketing manager Andy Ferrari.

Louisiana Pacific Corp. in Portland, Ore., set up its first wood-composite decking plant at ABT Co. in Selma, Ala., last month. “The next logical extension is fencing,” says product development manager Scott Sackinger.

Equipment suppliers have started to tailor products for wood-composite profiles. ESI Extrusion Services Inc. in Akron, Ohio, recently delivered its first downstream finishing chamber for wood-filled polyethylene deck and rail profiles. It has rotating brushes that create surface grooves resembling woodgrain. Fences could be its next application. ESI has also developed an in-line routing and cut-off system for standard plastic or wood-composite fence posts. Up to now, post holes for railings have been cut off-line with CNC routers.

Fencing Capacity Mushrooms

As an example of how PVC fencing operations are growing, Bufftech in Buffalo, N.Y., had one PVC fence profile plant when the company was bought by Certainteed in 1996. Certainteed has since converted one of its own pipe plants in McPherson, Kan., to fence extrusion and is adding fence capacity at another Certainteed plant in Social Circle, Ga.

In five years, Irwin Industries, Peachtree City, Ga., has expanded its PVC fence capacity from zero to 18 coextrusion lines, or 36 extruders. Twenty extruders were added in just the past six months. All fence production is now located at the company’s new plant in Bulls Gap, Tenn.

Outdoor Technologies Inc. of Macon, Miss. (part of Jancor Co., Perrysburg, Ohio), started making fence profiles 10 years ago. The firm now has 21 extruders running fencing and plans to add more capacity this year. Last year, it expanded fence fabrication and distribution in Sparks, Nev., and plans to start extruding there as well.

Royal Crown Ltd. (a unit of Royal Group Technologies Ltd.) in Milford, Ind., was originally a pipe maker called Chore-time/Brock. It developed a round post-and-rail fence for horses in 1982, followed by decks in ’89 and residential fences in ’94. In ’98 the firm moved to the new 129,000-sq-ft plant in Milford and plans a fourfold increase in production of all its monolayer profiles.

Vinyl Vision in Wilmington, Ohio, partly owned by Crane Products, is expanding from its one original fencing line to 10 monolayer systems and will move to a bigger plant.

Westech Fence in Mt. Vernon, Ind. (a unit of Westlake Group), doubled its fencing extrusion capacity last year through new equipment and conversion of capacity at other Westlake plants, like Engineered Profiles Ltd., a window-profile extruder in Calgary, Alberta.